create ()
returns an empty ivar, create_full
, a full one.
fill t v
fills t
with value v
if t
was empty. If t
was full, fill raises
an exception.
It is guaranteed that immediately after calling fill t
,
is_some (Deferred.peek (read t))
.
fill_if_empty t v
fills t
with v
if t
is currently empty. If t
is full,
then fill_if_empty
does nothing.
is_empty t
returns true if t
is empty
is_full t
returns true if t
is full
peek t
returns Some v
iff t
is full with value v
.
value_exn t
returns v
if t
is full with value v
, and raises otherwise.